3-amino-n-substituted succinamic acids and intermediates thereto

ABSTRACT

3-AMINO-N-SUBSTITUTED SUCCINAMIC ACIDS USEFUL IN VIEW OF THEIR POTENT SWEETENING PROPERTIES AND, IN ADDITION, THEIR PHARMACOLOGICAL ACTIVITY, E.G. ANTI-INFLAMMATORY.

United States Patent 3,803,223 3-AMlN0-N-SUBSTITUTED SUCCINAMIC ACIDS AND INTERMEDIATES THERETO Robert H. Mazur, Deerfield, and James M. Schlatter,

Glenview, 111., and Arthur H. Goldkamp, Bellevue, Wash., assignors to G. D. Searle & Co., Chicago, Ill. No Drawing. Filed July 20, 1970, Ser. No. 56,753 Int. Cl. C07c 101/12 US. Cl. 260--534 R 6 Claims ABSTRACT OF THE DISCLOSURE B-aminO-N-substituted succinamic acids useful in view of their potent sweetening properties and, in addition, their pharmacological activity, e.g. anti-inflammatory.

The present invention is concerned with novel derivatives of 3-aminosuccinamic acid which can be represented by the following structural formula wherein R is hydrogen or a methyl radical and R is a radical selected from the group consisting of -Alk-Y Alk being a lower alkylene radical, n a positive integer greater than 6 and less than 9, X being hydrogen or hydroxy, and Y a radical selected from the group consisting of cyclohexyl, naphthyl, furyl, pyridyl, indolyl and those of the formulas 0 (lower alkyl) wherein m is a member of the class consisting of 0 and l, t is a positive integer less than 3, V is hydrogen, a hydroxy, lower alkoxy,.3,4-methylenedioxy or halo radical in which the halogen possesses an atomic weight less than 36 with the provision that when V is hydrogen, Alk is a lower alkylene radical of greater than one carbon atom, or NRR' represents a 2-phenyl-B-methylmorpholino radical.

The lower alkylene radicals represented by Alk in the foregoing structural representation are typified by methylene, ethylene, trimethylene, tetramethylcne, pentamethylene and the corresponding branched-chain isomers.

Typical of the lower alkyl radicals encompassed in that structural formula are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl and the branched-chain isomers thereof.

The lower alkoxy radicals denoted in that formula are, for example, methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy and the branched chain groups isomeric therewith.

The compounds of this invention are conveniently obtained by a two-step process involving coupling of a suitable L-aspartic acid derivative, wherein protecting groups are attached to the amino and fl-carboxy groups, with the appropriate amine, followed by removal of the protecting groups, suitably by catalytic hydrogenolysis. Examples of suitable starting materials are fi-benzyl N- benzyloxycarbonyl-Laspartate and active esters thereof such as N-benzyloxycarbonyl-L-aspartic acid u-p-nitrophenyl, B-benzyl diester. When the starting material contains the free a-carboxy group, the reaction is carried out in the presence of an alkyl chloroformate and a suitable organic base. fl-Benzyl-N-benzyloxycarbonyl-L-aspartate is thus allowed to react, for example, with DL-l,4-dimethylpentylamine in the presence of isobutyl chloroformate and N-methylmorpholine to yield benzyl 3- benzyloxycarbonylamino N DL-1',4-dimethylpentyl- L-succinamate. The use of an active ester is exemplified by the reaction of N-benzyloxycarbonyl-L-aspartic acid p-nitrophenyl, 8-benzyl diester with DL-Z-amino-lphenylpropanol to afford benzyl 3-benzyloxycarbonylamino-N-DL-l'-methyl-2'-hydroxyphenethyl L succinamate.

Removal of the protecting groups of the aforementioned novel intermediates is most conveniently achieved by catalytic hydrogenolysis, preferably by use of a palladium black catalyst. When benzyl 3-lbenzyloxycarbonylamino-N-DL-1'-methyl-2'-hydroxyphenethyl L suc cinamate, for example, is shaken in methanol with hydrogen in the presence of palladium black at room temperature and about 3 atmospheres pressure, 3-amino-N- DL-1-methyl-2-hydroxyphenethyl-L-succinamic acid is produced.

An alternate process for production of the instant compounds utilizes the N-carboxy anhydride of L-aspartic acid as the starting material. That substance is prepared from L-aspartic acid by reaction with phosgene in dioxane according to the general procedure described by Farthing, A. C., J. Chem. Soc., 1950, 3213. The N-carboxy anhydride is coupled with the appropriate amine in aqueous medium at a pH of about 10 according to the general procedure described by Hirschmann et al., J. Org. Chem., 32, 3415 (1967). This alternate procedure ofiers the advantage of obviating the steps involving the addition and subsequent removal of protecting groups. A specific illustration is the reaction of L-aspartic acid N-carboxy anhydride with DL-1,4-dimethylpentylamine to afford 3- amino-N-DL-l',4'-dimethylpentyl-L-succinamic acid.

The 3-amino-N-substituted succinamic acids of the invention are surprisingly and unexpectedly characterized by a sweet taste, thus are useful for the purpose of imparting that taste to food products. These compounds can thus be added to food products such as fruits, vegetables, juices, meat products such as ham or bacon, sweetend milk products, egg products, salad dressings, ice creams and sherbets, gelatins, icings, syrups, cake mixes and beverages such as carbonated soft drinks and wines.

The preparation of a typical sweetened orange soda is described as follows:

A stock supply of bottlers syrup is prepared by mixing 5.5 ml. of a 50% aqueous citric acid solution with 150 ml. of water, dissolving 2 g. of 3-amino-N-DL-l',4'- dimethylpentyl-L-succinamic acid in that solution, adding successively 7.02 ml. of the orange flavor base manufactured by A. E. Illes, Dallas, Tex., labeled FO-7 8, and 2.7 g. of sodium benzoate and diluting that mixture to 200 ml. with water. One oz. samples of that bottlers syrup are transferred to 6 oz. bottles and ml. of cold tap Water is added to each bottle. To each bottle 42 ml. of cold charged bottling water (5 volumes carbon dioxide) is then added to achieve carbonation. Each bottle is capped and the contents mixed.

The latter preparation possesses a sweetness comparable to that containing a quantity of sucrose 50 times that of the name succinamic acid derivative.

The instant sweetening agents are stable substances and can be utilized in a variety of physical forms, e.g. as powders, tablets, syrups, etc. Liquid or solid carriers such as water, glycerol, starch, sorbitol, salt, citric acid and other suitable nontoxic substances can be used also. These agents are particularly useful as sugar substitutes for diabetics. They are, moreover, advantageous over synthetic sweetening agents such as saccharin and cyclamate by virtue of the absence of an unpleasant after-taste.

It has been determined that the sweetening property of the instant compounds is highly dependent upon the stereochemistry of the molecule. The corresponding D- aspartic acid and D-amine derivatives are thus totally lacking in that property.

The 3-amino-N-substituted succinamic acids of this invention are, furthenmore, useful as pharmacological agents, as is evidence, for example, by their anti-inflammatory properties. For that purpose, these substances can be administered in conventional pharmaceutical forms and by conventional routes. Solid forms such as pills, powders, capsules, tablets and the like and liquid forms such as syrups, emulsions, elixirs, suspensions and the like are suitable for oral administration, while aqueous solutions or suspensions or solutions in pharmacologically acceptable oil or oil-water emulsions are suitable for parenteral administration. Suitable excipients can also be added.

The pharmacological activity of the instant 3-amino-N- substituted succinamic acids is specifically illustrated by the anti-inflammatory response produced by the following representative compounds when administerer subcutaneously to rats at a dose of 25 mg.:

B-amino-N-D-1'methylphenethyl-L-succinamic acid 3-amino-N-L-1'-methylphenethyl-L-succinamic acid 3aminoN-phenethyl-L-succinamic acid 3-arnino-N-DL-1 -methyl-2'-hydroxyphenethyl-L- succinamic acid 3-amino-N-DL-1'-methylhexyl-L-succinamic acid 3amino-N-DL-1'-methyl-4"-hydroxyphenethyl-L- succinamic acid 3amino-N-DL-1'-ethylpentylL-succinamic acid S-amino-N-DL-1'4dimethylphentyl-L-succinamic acid.

The anti-inflammatory activity of the latter compounds was determined by the following assay:

Each of a group of 10 intact male rats Weighing 100- 130 grams is injected, under the plantar surface of each hind foot, with 0.1 ml. of a 1% solution of carrageenin (Type 402, Marine Colloids, Inc.). The test compound, dissolved or suspended in saline, corn oil or propylene glycol, is administered subcutaneously one hour prior to the carrageenin injection. Another such group serving as controls is treated in the identical manner save for omission of the test compound. The edema resulting from carrageenin injection is determined by measuring the circumference of the hind feet, in arbitrary units, 5 hours after the carrageenin injection and subtracting the average swelling of the group treated with the test compound from the average swelling of the control group. Compounds are rated active if they produce a significant decrease (P 0.05) in the swelling observed in control animals.

The invention will appear more fully from the examples which follow. These examples are set forth by way of illustration only and it will be understood that the invention is not to be construed as limited either in spirit or in scope by the details contained therein as many modifications both in materials and methods will be apparent from this disclosure to those skilled in the art. In these examples temperatures are given in degree centigrade C.) and quantities of materials in parts by weight unless otherwise noted.

EXAMPLE 1 A solution containing 17.85 parts of fi-benzyl N-benzyloxycarbonyl-L-aspartate, 5.9 parts by volume of N-methylmorpholine and 76.5 parts of anhydrous tetrahydrofuran is cooled to approximately 20 and 7 parts by volume of isobutyl chloroformate is added dropwise with vigorous stirring while the temperature is maintained between 10 and Stirring at that temperature is continued for about 5 minutes, at. the end of whichtime the mixture is cooled to approximately -30. At that point, 8.25 parts by volume of DL-1,4-dimethylpentylamine is added dropwise with vigorous stirring while the temperature is maintained between -10 and 15. After that addition is complete, the reaction mixture is kept at approximately 5 for about 16 hours. The reaction mixture is then diluted with ethyl acetate, washed successively with dilute hydrochloric acid, dilute aqueous sodium sulfate and dilute aqueous potassium bicarbonate, then dried over anhydrous sodium sulfate and stripped of solvent under reduced pressure. The resulting residual crude product is purified by trituration with hexane to afford benzyl 3-benzyloxycarbonylamino N DL-l,4'-dimethylpentyl L-succinamate, melting at about -l03. This compound exhibits an optical rotation, in methanol, of 7.

EXAMPLE 2 To a solution of 4.53 parts of DL-2-amino-1-phenylpropanol in 22.5 parts of dimethylformamide is added 15.06 parts of N-benzyloxycarbonyl-L-aspartic acid a-pnitrophenyl, fi-benzyl diester and the resulting reaction mixture is stirred for a few minutes until homogeneous, then is allowed to stand at room temperature for about 16 hours. At the end of that reaction period the mixture is diluted with ethyl acetate, then washed successively with dilute hydrochloric acid, water, dilute aqueous potassium bicarbonate and dilute aqueous sodium sulfate, and dried over anhydrous sodium sulfate, then stripped of solvent by distillation under reduced pressure. The residue thus obtained is triturated with cyclohexane to afford the crude product, melting at about 70-80 and that crude material is further purified by recrystallization from aqueous isopropyl alcohol to aiford benzyl 3-benzyloxycarbonyl amino-N-DL-1-methyl-2'-hydroxyphenethyl L succinamate, melting at about 72-84 and displaying an optical rotation, in methanol, of 9.

EXAMPLE 3 A mixture containing 4.9 parts of benzyl 3-benzyloxycarbonylamino-N-DL-1'-methyl 2' hydroxyphenethyl- L-succinamate, 0.5 part of palladium black and parts of methanol is shaken with hydrogen at room temperature and approximately 4 atmospheres pressure until 2 molecular equivalents of hydrogen have been absorbed. The catalyst is then removed by filtration and the methanol distilled under reduced pressure to afford the residual crude product. Purification of that material by trituration with ether yields pure S-amino-N-DL-l'-methyl2'-hydroxyphenethyl-L-succinamic acid, melting at about 188- 190. This compound exhibits an optical rotation, in water, of +10 and is represented by the following structural formula I NHtHCr EXAMPLE 4 The substitution of 3.99 parts of DL-Z-phenylcyclopropylamine in the procedure of Example 2 results in benzyl 3benzyloxycarbonylamino-N-DL-2-phenylcyclopropyl-L-succinamate, which, after recrystallization'from isopropyl alcohol, melts at about 80-92 and exhibits an optical rotation, in methanol, of 13.

EXAMPLE 5 The substitution of 5.84 parts of DL-2-phenyl-3-methylmorpholine and 10.71 parts of fi-benzyl N-benzyloxycarbonyl-L-aspartate in the procedure of Example 1 results in the ,B-benzyl ester of N-benzyloxycarbonyl-L-aspartic acid DL-2-phenyl-3methylmorpholide, which ex hibits an optical rotation, in methanol, of 35.

EXAMPLE 6 When 3.8 parts of DL-l-methylhexylamine and 10.71 parts of B-benzyl N-benzyloxycarbonyl-L-aspartate are allowed to react according to the procedure of Example 1, there is obtained, after recrystallization from cyclohexane-hexane, benzyl 3-benzyloxycarbonylaminoN-DL- 1'-methylhexy1-L-succinamate, melting at about 65-69 and exhibiting an optical rotation, in methanol, of --6.

EXAMPLE 7 The substitution of 4.53 parts of DL-lmethyl-4'-hy droxyphenethylamine in the procedure of Example 2 affords benzyl 3-benzyloxycarbonylamino-N-DL-l-methyl- 4-hydroxyphenethyl-L-succinamate, which, after recrystallization from cyclohexane, melts at about 106ll7 and exhibits an optical rotation, in methanol, of 9.5.

EXAMPLE 8 EXAMPLE 9 When 6.33 parts of n-heptylamine is substituted in the procedure of Example 1, there is produced, after recrystallization from isopropyl alcohol, benzyl 3-benzyloxycarbonylamino-N-n-heptyl L succinamate, melting at about 92-93 and exhibiting an optical rotation, in methanol, of 6".

EXAMPLE 10 The substitution of 6.33 parts of DL l-ethylpentylamine in the procedure of Example 1 results in benzyl 3-benyloxycarbonylamino-N-DL-1-ethylpentyl L succinamate, which, after recrystallization from hexane, melts at about 91-98 and exhibits an optical rotation, in methanol, of 9.

EXAMPLE 11 The reaction of.14.2 parts of DL-1-methyl-2-(2-thienyl)ethylamine, 28.6 parts of fi-benzyl N-benzyloxycarbonyl-L-aspartate, 8.72 parts of ethyl chloroformate and 18.8 parts by volume of N-methylmorpholine according to the procedure of Example 1 results in benzyl 3-benzyloxycarbonylamino-N-DL-1'-methyl 2 (2" thienyl) ethyl-L-succinamate.

EXAMPLE 12 When 7.1 parts of DL-l-methylheptylamine is substituted in the procedure of Example 1, there is produced, after recrystallization from hexane, benzyl 3-benzyloxycarbonyl amino-N-DL-1'-methylheptyl L succinamate, melting at about 78-82", and exhibiting an optical rotation, in methanol, of -3.

EXAMPLE 13 The reaction of 15.18 parts of DL-l-methyl-4'-fluorophenethylamine, 28.6 parts of flbenzyl N-benzyloxycarbonyl-L-aspartate, 8.72 parts of ethyl chloroformate and 19.3 parts of N-methylmorpholine according to the procedure of Example 1 results in benzyl 3-benzyloxycarbonylamino-N-DL-1-methyl 4" fluorophenethyl-L-succinamate, melting at about 82.587.

EXAMPLE 14 When 10.05 parts of N-benzyloxycarbonyl-L-aspartic acid a-p-nitrophenyl, fi-benzyl diester and 2.78 parts of phenethylamine are substituted in the procedure of Example 2, there is produced benzyl 3-benzyloxycarbonylamino-N-phenethyl-L-succinamate, which, after recrystallization from isopropyl acetate, melts at about 114-114.5 and exhibits an optical rotation, in methanol, of 10.5.

6. EXAMPLE 15 The reaction of 21.5 parts of N-benzyloxycarbonyl-L- aspartic acid fl-benzyl ester, 14.4 parts of Dbl-methyl- 3,4-dichlorophenethylamine, 6.54 parts of ethyl chloroformate and 14.5 parts by volume of N-methylmorpholine according to the procedure of Example 1 results in benzyl 3-benzyloxycarbonylamino-N-DL-1-methyl 3",4 dichlorophenethyl L succinamate, melting at about 92- 107".

EXAMPLE 16 When 28.6 parts of p-benzyl N-benzyloxycarbonyl-L- aspartate, 16.5 parts of DL-1-methyl-4'-chlorophenethylamine, 8.72 parts of ethyl chloroforrnate and 19.3 parts by volume of N-methylmorpholine are allowed to react according to the procedure of Example 1, there is produced benzyl 3-benzyloxycarbonylamino N DL 1- methyl-4"-chlorophenyl L succinamate, melting at about -106".

EXAMPLE 17 To a suspension of 150 parts of D-tartaric acid in 480 parts of methanol is added parts of DL-1,4-dimethylpentylamine and the resulting solution is allowed to stand at room temperature until crystallization is complete. The crystalline product is recrystallized several times from methanol .to afford optically pure D-1,4-dimethylpentylamine D-tartrate, melting at about 141143 and exhibiting an optical rotation, in methanol, of 19.5.

A solution of 26.5 parts of D-1,4-dimethylpentylamine D-tartrate in 8 parts of tetrahydrofuran containing 8 parts of water is diluted with approximately180 parts of tetrahydrofuran and 10.6 parts by volume of 50% aqueous sodium hydroxide is added. The mixture is shaken; 200 parts of potassium carbonate is added, and the mixture is filtered. The filter cake is Washed with tetrahydrofuran and the combined filtrates containing the free amine are used in the next step.

The tetrahydrofuran solution containing 11.5 parts of D-1,4-dimethylpentylamine is allowed to react with 35.74 parts of B-benzyl N-benzyloxycarbonyl-L-aspartate according to the procedure of Example 1, thus affording benzyl 3 benzyloxycarbonylamino-N-D-1,4 dimethylpentyl-L-succinamate, which, after recrystallization from aqueous isopropyl alcohol, melts at about 116-117 and exhibits an optical rotation, in methanol, of 4.

EXAMPLE 18 The resolution of DL-l-methylhexylamine according to the procedure described in Example 17 results in D-lmethylhexylamine tartrate, melting at about 107110 and exhibiting an optical rotation, in methanol, of 20.

The latter salt is converted by the procedure described in Example 17 to 3.45 parts of D-l-methylhexylamine and that amine is allowed to react with 10.72 parts of fl-benzyl N-benzyloxycarbonyl-L-aspartate according to the procedure described in Example 1, thus affording benzyl 3-benzyloxycarbonylamino N D 1'-methylhexyl-L-succinamate which, after recrystallization from aqueous isopropyl alcohol, melts at about 98-100 and displays an optical rotation, in methanol, of 4.

EXAMPLE 19 To a suspension of parts of L-tartaric acid in 480 parts of methanol is added 115 parts of DL-l-methylhexylamine and the resulting solution is allowed to stand at room temperature until crystallization is complete. Those crystals are collected by filtration and recrystallized several times from methanol to afford optically pure L-lmethylhexylamine L-tartrate, melting at about 108-1 10 and exhibiting an optical rotation, in methanol, of +19.

The latter salt is converted to the free amine by the procedure described in Example 17 and 3.45 parts of that amine, i.e. L-l-methylhexylamine, is allowed to react with 10.7 parts of j8-benzyl N-benzyloxycarbonyl-L-aspartate according to the procedure described in Example 1 to 7 afford benzyl 3 benzyloxycarbonylamino-N-L-1-methylhcxyl-L-succinamate, which, after recrystallization from aqueous isopropyl alcohol, melts at about 96-99 and exhibits an optical rotation, in methanol, of -11.

EXAMPLE 20 To a suspension of 150 parts of L-t'artaric acid in 480 parts of methanol is added 115 parts of DL-1,4-dimethylpentylamine and the resulting solution is allowed to stand at room temperature until crystallization is complete. The crystalline salt is recrystallized several times from methanol to afford optically pure L-1,4dimethylpentylamine L-tartrate, melting at about 142144 and exhibiting an optical rotation, in methanol, of +20.

The latter salt is converted to the free amine by the procedure described in Example 17 and 5.98 parts of that amine, i.e. L-l,4dimethylpentylamine, is allowed to react with 17.8 parts of B-benzyl N-benzyloxycarbonyl-L-aspartate to afford benzyl 3-benzyloxycarbonylamino N-L-l', 4' dimethylpentyl-L-succinamate, which after recrystallization from aqueous isopropyl alcohol, melts at about 105-107" and exhibits an optical rotation, in methanol, of l3.

EXAMPLE 21 The reaction of 6.6 parts of Z-indanyla-mine with 17.73 parts of fl-benzyl N-benzyloxycarbonyl-L-aspartate according to the procedure of Example 1 results in benzyl 3 benzyloxycarbonylamino-N-2'-indanyl-L-succinamate, which after recrystallization from isopropyl alcohol, melts at about 122-126".

EXAMPLE 22 The reaction of 5.75 parts of DL-l,3-dimethylpentylamine with 17.8 parts of fi-benzyl N-benzyloxycarbonyl- L-aspartate according to the procedure of Example 1 aifords benzyl 3abenzyloxycarbonylamino-N DL-1',3'-dimethylpentyl-L-succinamate, melting at about 61-7l and exhibiting an optical rotation, in methanol, of +105 EXAMPLE 23 The reaction of 3.11 parts of D-l-methylphenethylamine with 10.05 parts of N-benzyloxycarbonyl-L-aspartic acid a-p-nitrophenyl, ,B-benzyl diester according to the procedure of Example 2 affords benzyl 3-benzyloxycarbonylamino-N-D-1-methylphenethyl L succinamate, which, after recrystallization from isopropyl acetate, melts at about 108-1095 and exhibits an optical rotation, in methanol, of +3.5".

EXAMPLE 24 -When 3.11 parts of L-l-methylphenethylamine is allowed to react with 10.05 parts of N-benzloxycarbonyl- L-aspartic acid u-p-nitrophenyl, B-benzyl diester according to the procedure of Example 2, there is produced benzyl 3-benzyloxycarbonylaminoN-L-1' methylphcnethyl-L succinamate, which, after recrystallization from isopropyl acetate, melts at about 118-1205 and displays an optical rotation, in methanol, of -23.5.

EXAMPLE 25 The reaction of 6.16 parts of DL-l-ethylphenethylamine with 19.05 parts of N-benzyloxycarbonyl-L-aspartic acid a-p-nitrophenyl, fi-tbenzyl diester according to the pro cedure of Example 2 results in benzyl 3-benzyloxycarbonylamiho N DL-l' ethylphenethyl-L-succinamate which, after recrystallization from isopropyl acetatecyclohexane, melts at about -1l5 and exhibits .an optical rotation, in methanol, of 11.

EXAMPLE 27 When 5.58 parts of 2-cyclohexylethylamine is allowed to react with 20.1 parts of N-benzyloxycarbonyl-L-aspartic acid a-p-nitrophenyl, 13-benzyl diester by the procedure of Example 2, there is produced benzyl 3-benzyloxycarbonylamino N 2' cyclohexylethyl L succinamate, which after recrystallization from isopropyl acetate, melts at about 129.5-130.5 and exhibits an optical rotation, in methanol, of 2.5'.

EXAMPLE 28 When 6.86 parts of 4-hydroxyphenethylamine and 20.1 parts of N-benzyloxycarbonyl-L-aspartic acid a-p-nitrophenyl, B-benzyl diester are allowed to react according to the procedure of Example 2, there is produced benzyl 3- benzyloxycarbonylamino N 4' hydroxyphenethyl L- succinamate, which, after recrystallization from isopropyl acetate-cyclohexane, melts at about 148-149.5 and exhibits an optical rotation, in methanol, of -12.

EXAMPLE 29 The reaction of 6.11 parts of 2-(2-pyridyl)-ethylamine with 20.1 parts of N-benzyloxycarbonyl-L-aspartic acid a-p-nitrophenyl, fi-benzyl diester by the procedure of Example 2 results in benzyl 3-benzyl-oXycarbonylamino-N- 2-(2"-pyridyl)ethyl-L-succinamate, which, after recrystallization from carbon tetrachloride, melts at about 97- 105 and exhibits an optical rotation, in methanol, of 10.

EXAMPLE 30 When 9.33 parts of DL-Z-methylphenethylamine is allowed to react with 30.15 parts of N-benzyloxycarbonyl- L-aspartic acid a-p-nitrophenyl, ii-benzyl diester by the procedure 01 Example 2, there is produced benzyl 3- benzyloxycarbonylamino N DL 2' methylphenethyl- L-succinamate, which, after recrystallization from isopropyl acetate, melts at about 72-8l and exhibits an optical rotation, in methanol, of 15.5

EXAMPLE 31 The reaction of 5.5 parts of l,l-dimethyl-4'-chlorophenethylamine with 14.34. parts of N-benzyloxycarbonyl-L- aspartic acid a-p-nitrophenyl, fl-benzyldiester according to the procedure of Example 2 results in benzyl 3-benzyloxycarbonylamino N 1',1' dimethyl 4" chlorophenethyl-L-succinamate.

EXAMPLE 33 EXAMPLE 33 The reaction of 6.76 parts of N-methylphenethylamine with 17.58 parts of fi-benzyl N-benzyloxycarbonyl-L- aspartate by the procedure of Example 1 affords benzyl 3 benzyloxycarbonylamino N methyl N phenethyl- L-succinamate as an oil, which exhibits an optical rotation, in methanol, of 22.

EXAMPLE 34 The reaction of 4 parts of dl-l-niethyl-Z-(3'-indolyl)- ethylamine with 11 partsof N-benzyloxycarbonyl-L-aspartic acid a-p-nitrophenyl, p-benzyl diester by the procedure described in Example 2 results in benzyl 3-benzyloxycarbonylamino N [d-l methyl 2-(3"-indolylethyl) ]-L-succinamate, which, after recrystallization from 9 ethyl acetate, melts at about 158-162 and exhibits an optical rotation, in methanol, of |2 and benzyl 3-benzyloxycarbonylamino N [I l methyl 2' (3" indolylethyl)]-L-succinamate, which, after recrystallization from isopropyl alcohol, melts at about l02-l08 and exhibits an optical rotation, in methanol, of 15.

EXAMPLE 35 The reaction of 8.86 parts of d-N-methylglucamine with 1435 parts of N-benzyloxycarbonyl-L-aspartic acid a-pnitrophenyl, fl-benzyl diester by the procedure described in Example 2 affords benzyl 3-benzyloxycarbonylamino- N-methyl-N-d-glucosyl-L-succinamates an oil, displaying an optical rotation, in methanol, of -24.5.

EXAMPLE 36 When 8.2 parts of D-N-methyl-l-methylphenethylamine is substituted in the procedure of Example 1, there is obtained, as an oil, benzyl 3benzyloxycarbonylamino-N- methyl-N-D-1'-methylphenethyl-L-succinmate.

EXAMPLE 37 When 8.2 parts of L-N-methyl-l-methylphenethylamine is substituted in the procedure of Example 1, there is obtained, as an oil, benzyl 3benzyloxycarbonylamino-N- methyl-N- -1-mthylphnethyl L-succinamat.

EXAMPLE 38 The substitution of 8.52 parts of D-N-methyl-l-methyl- 2-cyclohexylethylamine in the procedure of Example 1 results in benzyl 3benzyloxycarbonylamino-N-methyl-N- D-1'-methy1-2' cyclohexylethyl-L-succinamate, obtained as an oil.

EXAMPLE 39 The substitution of 8.52 parts of L-N-methyl-l-methyl- 2-cyclohexylethylamine in the procedure of Example 1 results in benzyl 3benzyloxycarbonylamino-N-methyl-N- L 1'-methyl-2-cyclohexylethyl-L-succinamate, obtained as an oil.

EXAMPLE 40 The reaction of parts of DL-1-methyl-2-(2'-furyl) ethylamine hydrochloride with 30.15 parts of N-benzyloxycarbonyl-L-aspartic acid a-p-nitrophenyl, ,8-benzyl diester and 5.84 parts of triethylamine according to the procedure of Example 2 results in benzyl 3-benzyloxycarbonylamino-N-DL 1 methyl-2'-(2"-furyl)ethyl-L-succinamate.

EXAMPLE 41 When 6.49 parts of DL-1methyl-3-ethoxy-n-propylamine is allowed to react with 19.8 parts of fl-benzyl N- benzyloxycarbonyl-L-aspartate by the procedure described in Example 1, there is produced benzyl 3-benzyloxycarbonylamino-N-(DL-l-methyl 3' ethoxy-n-propyl)-L- succinamate, melting at about 64-81 and exhibiting an optical rotation, in methanol, of 7.5.

EXAMPLE 42 The reaction of 8.96 parts of DL-1-methyl-2-(3,4' methylenedioxyphenyl)ethylamine with 17.58 parts of .13- benzyl N-benzyloxycar'bonyl-L-aspartate by the procedure described in Example 1 results in benzyl 3-benzyloxycarbonylamino-N-[DL 1' methyl-2-(3",4"-methylenedioxyphenyl)ethyl]-L-suocinamate, which, after reerystal lization from isopropyl alcohol, melts at about 113-1 19 and exhibits an optical rotation, in chloroform, of +10".

EXAMPLE 43 When 8.32 parts of 4-methoxyphenethylamine is allowed to react with 23.9 parts of N-benzyloxycarbonyl-L- aspartic acid a-p-nitrophenyl p-benzyl diester according to the procedure of Example 2, there is produced benzyl 3 benzyloxycar bonylamino-N 4-methoxyphenethyl-L- succinamate, which after recrystallization from isopropyl acetate, melts at about 1355-1365".

EXAMPLE 45 The reaction of 695 parts of 4-flu0rophenethylamine with 23.9 parts of N-benzyloxycarbonyl-Laspartic acid a p-nitrophenyl, B- benzyl diester by the procedure described in Example 2 results in benzyl 3-benzyloxycarbonylamino- N-4fiuorophenethyl-L-succinamate, which, after recrystallization from toluene, melts at about 106-108 and exhibits an optical rotation, in methanol, of 9.

EXAMPLE 46 When 5.56 parts of 2-(2'-furyl)ethylamine is allowed to react with 23.9 parts of N-benzyloxycarbonyl-L- aspartic acid a-p-nitrophenyl fl-benzyl diester by the procedure described in Example 2, there is produced benzyl 3-benzyloxycarbonylamino-N [2 (2" furyl)ethyl]- L-succinamate, which, after recrystallization from isopropyl alcohol, melts at about 105 and exhibits an optical rotation, in methanol, of 10.

EXAMPLE 47 The reaction of 6.85 parts of Z-phenoxyethylamine with 23.9 parts of N-benzyloxycarbonyl-L-aspartic acid a-pnitrophenyl, B-benzyl diester by the procedure of Example 2 results in benzyl 3benzyloxycarbonylamino-N-2- phenoxyethyl-L-succinamate, which, after recrystallization from isopropyl acetate, melts at about 101-103" and ex-- hibits an optical rotation of 5.5 in methanol.

EXAMPLE 48 When 4.48 parts of 1,1-dimethylphenethylamine is allowed to react with 14.34 parts of N-benzyloxycarbonyl- L-aspartic acid a-p-nitrophenyl, fl-benzyl diester by the procedure described in Example 2, there is produced benzyl 3 benzyloxycarbonylamine-N 1',1 dimethylphenethyl-L-succinamate.

EXAMPLE 49 When 4.72 parts of benzyl 3-benzyloxycarbonylamino- N-DL-2'-phenylcyclopropyl-L-succinamate is substituted in the procedure of Example 3, there is produced 3-amino- N-DL-2'-phenylcyclopropyl-L-succinamic acid, which, after recrystallization from aqueous isopropyl alcohol, melts at about -178 and exhibits an optical rotation, in methanol, of +5 EXAMPLE 50 The substitution of an equivalent quantity of the ,8- benzyl ester of N-benzyloxycarbonyl-L-aspartic acid a- DL-2-phenyl-3-methylmorpholide in the procedure of Example 3 results in L-aspartic acid a-DL 2 phenyl-3- methylmorpholide, which softens at about 145 and exhibits an optical rotation, in acetic acid, of 15.9.

EXAMPLE 51 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N-DL-1'-methylhexyl-L-succinamate is substituted in the procedure of Example 3, there is produced 3 amino-N-DL-1'-methylhexy1-L-succinamic acid, Which after recrystallization from water, melts at about 194 and exhibits an optical rotation, in acetic acid, of +6.9.

EXAMPLE 52 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino N DL-1-methyl-4"-hydroxyphenethyl- L-succinamate is substituted in the procedure of Example W 11 3, there is obtained 3-amino-N-DL-l'-methyl-4"-hydroxyphenethyl-L-succinamic acid, which softens atabout 160 and exhibits an optical rotation, in water, of +5 EXAMPLE 53 The substitution of'an equivalent quantity of benzyl 3- benzyloxycarbonylamino-N-n-heptyl-L-succinamate in the procedure of Example 3 affords 3-amino-N-n-heptyl-L- succinamic acid, melting at about 186-188 and exhibiting an optical rotation, in methanol, of 8.

EXAMPLE 54 By substituting an equivalent quantity of benzyl 3- benzyloxycarbonylamino N DL-1'-ethylpenty1-L-succinamate in the procedure of Example 3, there is obtained 3 amino-N-DL-1'-ethylpentyl-L-succinamic acid, which after recrystallization from aqueous acetone, melts at about 201-202 and exhibits an optical rotation, in acetic acid, of +9.

EXAMPLE 55 By substituting an equivalent quantity of benzyl 3- benzyloxycarbonylamino N-DL-l',4'-dimethylpentyl-L- succinamate and otherwise proceeding according to ,the processes described in Example 3, there is produced 3- amino N DL-l',4-dimethylpentyl-L-succinamic acid, melting at about 181-188 and displaying an optical rotation, in methanol, of

EXAMPLE 5 6 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N-DL-l-methylheptyl-L-succinamate is substituted in the procedure of Example 3, there is obtained, after recrystallization from aqueous acetone, 3-amino-N- DL-1-methylheptyl-L-succinamic acid, melting at about 21l-2l2 and displaying an optical rotation,in methanol, of --7.5

EXAMPLE 57 The substitution of an equivalent quantity of benzyl 3- benzyloxycarbonylamino N D-l',4'-dimethylpentyl-L- succinamate in the procedure of Example 3 results in-3- amino-N-D-l',4'-dimethylpentyl-L-succinamic acid, which, after recrystallization from aqueous methanol, melts at about 210-213 and displays an optical rotation, in methanol, of -3.

EXAMPLE 58 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N-D-l-methylhexyl-L-succinamate is substituted in the procedure of Example 3, there is produced 3 amino-N-D-l'-methylhexyl-L-succinamic acid, which, after recrystallization from aqueous methanol, melts at about 217-218 and displays an optical rotation, in l N hydrochloric acid, of +16". t

EXAMPLE 59 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N-L-l'-methylhexyl-L-succinamate is substi-. tuted in the procedure of Example 3, there is obtained 3- ann'no-N-L-1-methylhexyl-L-succinamic acid, which, after recrystallization from water, melts at about 187-189 and displays an optical rotation, in methanol, or -5.

EXAMPLE 60 I When an equivalent quantity of benzyl 3-benzyloxycarbonylamino N L-l,4'-dimethylpentyl-L-sUccinamate is substituted in the procedure of Example 3, there is obtained 3. amino N-L-1,4'-dimethylpentyl-L-succinamic acid, melting at about 187-190 and displaying an optical rotation, in water, of +20".

EXAMPLE 61 The substitution of an equivalent quantity of benzyl 3- 'benzyloxycarbonylarnino N-2'-indanyl-L succinamate in the procedure of Example 3, affords 3-amino-N-2 -indanyl-L-succinamic acid, which, after recrystallization from aqueous methanol, melts at about 2l4-224 and exhibits an optical rotation, in l N hydrochloric acid, of 5.5.

EXAMPLE 62.

When an equivalent quantity of benzyl 3-benzyloxycarbonylamino N-DL-1,3'-dimethylpentyl-L-succinamate is substituted in the procedure of Example 3, there is produced, after recrystallization from water, 3-amino-N-DL- l',3'-dimethylpentyl-L-succinamic acid, melting at about 162-l66 and exhibiting an optical rotation, in methanol, of 6.

EXAMPLE 63 EXAMPLE 65 By substinting an equivalent quantity of benzyl 3-benzyloxycarbonylamino N-methyl-N-D-l'- methyl2-cyclohexylethyl-L-succinamate and otherwise proceeding ac cording to the processes of Example 3, there is obtained 3- amino-N-Inethyl-N-D-l'-rnethyl-2' cyclohexylethyl L succinamic acid, melting at about 194-196 and exhibiting an optical rotation, in water, of +1 EXAMPLE 66 The substitution of an equivalent quantity of benzyl 3-benzyloxycarbonylamino N-methyl-N-L-1-methyl-2- cyclohexylethyl-L-succinamate in the procedure of Exampe 3 results in 3-arnino-N-methyl-N-L-l-methyl-2'- cyclohexylethyl-L-succinamic acid, which, after recrystallization, from isopropyl' alcohol-ether, metals at about l79-180 and exhibits an optical rotation, in Water of =13.5.

- EXAMPLE 67 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N-DL- '-methyl-2-(x-naphthyl)- ethyl-L succinamate is hydrogenolyzed according to the procedure of Example 3, but utilizing 75% acetic acid as a solvent, 3 amino- N DL 1-methyl-2l-(a-naphthyDethyl-L succinamic acid, which, aiter recrystallization from methanol-ether, melts at about 156-160", is produced.

EXAMPLE 68 The substitution of an equivalent quantity of benzyl 3- benzyloxycarbonylamino-N-DL-l'-methyl 4" fluorophenethyl-L-succina-mate in the procedure of Example 3 results in 3-amino-N-DL-1-methyl-4"-fiuorophenethylL- succinamic acid, which, after recrystallization from water, melts at about 2025-2045 EXAMPLE 69 By substituting an equivalent quantity of bendyl 3-benzyloxycarbonylamino-N-DL-l -methyl 3",4" dichlorophenethyl-L-succinamate and otherwise proceeding according to the processes of Example 3, there is produced 3-amino-N-DL 1' methyl-3", -dichlorophenethyl-L- succinamic acid. v

' EXAMPLE 70 The substitution of an equivalent quantity of benzyl 3- benzyloxycarbonylamino-N-DL-1'-methyl 4" chlorophenethyl-L-succinamate in the procedure of Example 3,

13 results in 3-amino-N-DL-1'-methyl 4"-chlorophenethyl- L-succinamic acid. l

EXAMPLE 71 The substitution of an equivalent quantity of benzyl 3- benzyloxycarbonylamino-N-DL-l,-methyl-2-(2" furyl) ethyl-L-succinamate in the procedure of Example 3 results in 3 amino N-DL-1-methyl-2 '-(2"-furyl)ethyl-L-succinamic acid, which, after recrystallization from methanolether, melts at about 168180.

EXAMPLE 7?.

When an equivalent quantity of benzyl 3-benzyloxycarbonylaminQ-N-DL Z'-methylphenethyl-L succinamate is substituted in the procedure of Example 3, there is produced 3 amino-N-DL-2-methylphenethyl-L-succinamic acid, which, after recrystallization from water, melts at about 182-188" with decomposition and displays an optical rotation, in water, of 15.

EXAMPLE 73 3 a When an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N-(DL-l'-methyl-3'-ethoxy-n-propyl) L- succinamate is substituted in the procedure of Example 3, there is obtained 3 amino-N-(DL-1'-methyl-3'-ethoxy-npropyl)-L-succinamic acid, which, after recrystallization from methanol-ether, melts at about 166l70 with decomposition and displays an optical rotation,'in methanol, of +2.5

EXAMPLE 74 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino N methyl-N-phenethyl-L-succinamate is substituted in the procedure of Example 3, there is produced 3-amino-N-methyl-N-phenethyl-L-succinamic acid, which, after recrystallization from methanol, melts at about 173-175 and displays an optical rotation, in methanol, of -3l.

EXAMPLE 75 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino N [DL-1-methyl-2'-(3, -methy]enedioxyphenyl)ethyl]-L-succinamate is substituted in the procedure of Example 3, there is produced 3-a-mino-N- [DL-l-methyl-2- (3 ",4" methylene-dioxyphenyl)ethyl]- L-succinamic acid, melting at about 189-192 with decomposition and exhibiting an optical rotation, in methanol, of +5.5 l g EXAMPLE 76 The substitution of an equivalent quantity of benzyl 3- benzyloxycarbonyla-mino N (DL-l'-methyl-3'-phenyln-propyl)-L-succinamate in the procedure of Example 3 results in 3-amino-N-(DL-1-methyl-3'-phenyl-n-propyl)- L-succinamic acid, which, after recrystallization from aqueous methanol, melts at about 190196 with decomposition and exhibits an optical rotation, in 0.1 N hydrochloric acid, of +l5.5.

EXAMPLE 77 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino N 4-methoxyphenethyl-L-succinamate is substituted in the procedure of Example 3 there is obtained 3 amino-N-4-'-methoxyphenethyl-L succina-mic acid, which, after recrystallization from aqueous methanol, melts at about 2l1-213 with decomposition and exhibits an optical rotation, in 1 N hydrochloric acid, of 36 EXAMPLE 7:; ,7

The substitution of an equivalent quantity of benzyl 3- benzyloxycarbonylamino N 4' fluorophenethyl-L-succinamate in the procedure of Example 3 results in 3- amino N 4-fluorophenethyl-L-succinamic acid, which, after recrystallization from water, melts at about'208- 209 with decomposition and exhibits an optical rotation, in methanol, of -6.

14 EXAMPLE 79 By substituting an equivalent quantity of benzyl 3- benzyloxycarbonylamino N [2-(2'-furyl)ethyl]-L-succinamate and otherwise proceeding according to the processes of Example 3, there is obtained 3-amino-N-[2-(2'- furyl)ethyl];L-succinamic acid, which, after recrystallization from methanol, melts at about 196 with decomposition and exhibits an optical rotation, in methanol, of 16.5.

EXAMPLE 80 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino N l',1'-dimethyl-4"-chlorophenethyl-L- succinamate is hydrogenolyzed in 75% acetic acid by the procedure described in Example 3, there is produced 3- amino N-1',1'-dimethyl-4"-chlorophenethyl-L-succinamic acid.

EXAMPLE 81 The hydrogenolysis of an equivalent quantity of benzyl 3 'benzyloxycarbonylamino N-D-l-methylphenethyl-L- succinamate in 75% acetic acid by the procedure described in Example 3 results in 3-amino-N-D-1-methylphenethyl-L-succinamic acid, which, after recrystallization from aqueous ethanol, melts at about 222-225 with decomposition and exhibits an optical rotation, in water, of ;+14.

EXAMPLE 82 When an equivalent quantity of benzyl 3-benzyloxycarbonylaminoN-L-1'-methylphenethyl-L-succinamate is hydrogenolyzed in 75% acetic acid by the procedure described in Example 3, there is obtained 3-amino-N-L-1'- methylphenethyl-L-succinamic acid, which, after recrystallization from water, melts at about 197198 with decomposition and displays an optical rotation, in methanol, of 12.

EXAMPLE 83 The hydrogenolysis of an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N-phenethyl-L-succinamate in 75% acetic acid by the procedure described in Example 3 results in 3 amino N-phenethyl-L-succinamic acid, which, after recrystallization from aqueous isopropyl alcohol, melts at about 212-214 with decomposition and exhibits an optical rotation, in water, of 14.5.

EXAMPLE 84 .When an equivalent quantity of benzyl 3-benzyloxycarbonylamino N-L-1-methyl-2'-cyclohexylethyl-L-succinamate is hydrogenolyzed in 75 acetic acid according to the procedure described in Example 3, there is produced 3 amino-N-L-1-methyl-2'-cyclohexylethyl-L-succinamic acid, which, after recrystallization from aqueous ethanol, melts at about 184-185 with decomposition and exhibits an optical rotation, in methanol, of -19.

EXAMPLE 85 v succinamic acid, which, after recrystallization from aqueous methanol, melts at about l93202 with decomposition andexhibits an optical rotation, in acetic acid, of 16.5.

EXAMPLE 87 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino N-2'-(2"-pyridyl)ethyl-L-succinamate is hydrogenolyzed in 75% acetic acid by the procedure described in Example 3, there is obtained 3-amino-N.-2-

(2"-pyridyl)ethyl-L-succinamic acid, which, after recrys tallization from water, melts at about ZOO-202 with decomposition and exhibits an optical rotation, in water,

EXAMPLE 88 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N-DL-l'-ethylphenethyl-L-succinamate is hydrogenolyzed in 75% acetic acid by the procedure described in Example 3, there is produced B-amino-N-DL- 1'-ethy1phenethyl-L-succinamic, acid, which, after recrystallization from methanol-ether, melts at about 158-163 with decomposition and exhibits an optical rotation, in methanol, of ,+7.8.

EXAMPLE 89 When an equivalent quantity of benzyl S-benzyloxyearbonylamino-N-4'-hydroxyphenethyl-L-succinamate is bydrogenolyzed in 75% acetic acid by the procedure described in Example 3, there is produced 3-amino-N-4'- hydroxyphenethyl-L-succinamic acid, which, after recrystallization from water, melts at about 209-210 with decomposition and exhibits an optical rotation, in water, of --21.

EXAMPLE 90 By substituting an equivalent quantity of D-l-methylcyclohexyl'ethylamine and otherwise proceeding according to the processes described in Example 2, there is produced benzyl 3-benzyloxycarbonylamino-N-D 1'-methylcyclohexylethyl-L-succinamate, which, after recrystallization from hexane-ether, melts at about 69-81 and exhibits an optical rotation, in methanol, of +2.0".

EXAMPLE 91 When an equivalent quantity of 1,1-dimethylphenethylamine is substituted in the procedure of Examplel, there is obtained an oily product, which is extracted with ether. The ether extract is stripped of solvent to aiford,as an oil, benzyl 3 benzyloxycarbonylamino-N-1',1'-dimethylphen thyl-L-succinamate, exhibiting an optical rotation of 6, in methanol.

EXAMPLE 92 7 When an equivalent quantityfiof DL-l-methyl-Z-phenoxyethylamine is substituted in the procedure of Example 2, there is produced benzyl 3-benzyloxycarb'onyl amino-N-DL-1'-methyl 2'phenoxyethyl-IL-succinamate melting at about 76-88" and exhibiting optical rotation, in chloroform, of +13.S.

EXAMPLE 93 e By substituting an equivalent quantity ofDL-l-me'thyl 3-methoxy-n-propylamir1e and otherwise proceeding according to the processes of Example 2, there is obtained benzyl 3-benzyloxycarbonylamino-N-DL-l-methyl 3' inethoxy-n-propyl-L-succinamate, which exhibits an' optical rotation of 7.5 in methanol.

EXAMPLE 94 When an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N-Z'-phenoxyethyl L succina-r'nate is substituted in the procedure of Example 3, except that 90% acetic acid is used as the solvent, 3,-amino-N -2- pheuoxyethyl-L-succinamic acid is produced. After re,- crystallization from water, that material melts with decomposition at 184-185 and exhibits an optical rotation, in 1 N hydrochloric acid, of -13.

EXAMPLE 95 When an equivalent quantity of benzyl S-benZyIZoXycarbonylamino-N-D-l-methylcyclohexyl L succinamat'e is substituted in the procedure of Example 3, there is produced B-amino-N-D-1-rnethylcyclo L succinamic acid, which, after recrystallization from aqueous -metha-' nol, melts at about 207-208 with elferv escence and'exhibits an optical rotation, in methanol, of +16".

EXAMPLE 96 The substitution of an equivalent quantity of benzyl 3: benzyloxycarbonylamino N l,1'-dimethylphenethy1-L succinamate in the procedure of Example 3 atfo rds' amino-N-1,1 dimethylphenethyl L succinamic acid, which, after recrystallization from water, melts at about l59-161 and exhibits an optical rotation of 15.5 in methanol.

EXAMPLE 97 The substitution of an equivalent quantity of benzyl 3-benzyloxycarbonylamino-N- -1-[(4' hydroxybenzyl)- Z-hydroxy]ethyl-L-succinamate in the procedure of Example 3 results in 3-amino-N-L-1-[(4'-hydroxybenzyl)-2-hydroxy]ethyl-L-succinamic acid, melting at about 212- 213-.5 with decomposition.

What is claimed is:

1. A compound of the formula 00011 (I311: CIJH-NH: (J -N EZC nH: n+t O whereinn is a positive integer greater than '6 and less than 9.

2. As in claim 1, a compound of the formula CR: oH-NH,

3. Asia claim 1, the compound is 3-amino-N-DL-1- methylhexyl-L-succinamic acid.

4. As in claim 1, the compound which is 3-amino-N- DL-1,4-dimethylpentyl-L-succinamic acid.

5, As in claim 1, the compound which is 3-amino-N-L 1, '-di'methylpentyl L-succinamic acid.

GHAs in claim 1, the compound'whichis 3-au1inoN-L- 1-methylhexyl-L- succinamic acid.

q I "References Cited Liwschitz, Y. et al.: JACS, vol. 78 (3069-72), 1956.

LORRAINE A. WEINBERGER, Primary Examiner P. J. KFLLOS, Assistant Examiner I US. Cl. X.R.

99-79, 141 A; 260247.2- A, 295 AM, 295 CA, 326.14 R, 332.2 A, 340.5, 347.3, 347.4, 468 E, 471 c, 482 c, 501.1, 514 J, 518 R, 518 A, 519-, 534 M; 424-319 

